The present invention is directed to a dental handpiece that contains a grip part having a non-slip surface.
Apart from a few exceptions, dental handpieces are usually held in the fashion of a pencil, for example in a three-finger hold or grip. The surface design in the region of the finger hold, which region is referred to as a gripping region, plays a particular part with the quality of the grip.
For hygienic reasons, particularly because of easy cleaning of the surface of the handpiece, first, one aim is that the entire handpiece should comprise an optimally smooth surface. On the other hand, it is necessary to have adequate gripability in the gripping region to enable the handpiece to lie securely in the hand during a preparation without great finger pressure. This is true both with respect to turning as well as with respect to longitudinal slippage under the influence of axial and radial forces that act on the drill during the use of the drill.
In order to meet these contradictory demands, it has already been proposed to provide a plurality of trough-shaped flattened portions or depressions uniformly distributed over the circumference of the handpiece in the gripping region. Such an arrangement is disclosed in European Patent Application EP-A-00 17 861. With the aim of reducing the manufacturing cost for the surface fashioning of the handpiece, it has also been proposed, in European Patent Application EP-A-00 54 653, to provide the surface of the handpiece in the gripping region with a carrier layer in which grains of a defined size are embedded. The handpiece will exhibit a certain roughness and, thus, gripability in the gripping region.
Although good gripability is obtained with this surface design, the problem or, respectively, the question whether such a surface is not too anti-slip is raised to a great extent, particularly in view of the greater and greater demand currently occurring for the wearing of rubber gloves when using a dental handpiece.